Our eldest is in such a rush to meet his girlfriend that he can barely stop to spend half an hour to marvel at why I won't give him £1.20 for the train, even though of course he's the one with a bankful of money from his lucrative weekend job misselling computer accessories over the phone, while we are still reeling from the shock of our so-called endowment 'provider' deciding that on second thoughts they won't be paying off our mortgage in 2012 after all, owing to the dog having eaten their maths homework back in 1987.

All of which has resulted in some emergency financial remodelling that lumbers us with monthly outgoings exceeding earnings by - as it happens - exactly £1.20, which is impossible to chip away at without living on catfood and yet which miraculously balloons out of control the minute one of us so much as steps into a pub.

So I'm afraid we all have to tighten our belts, I tell the boy, and if that seems unfair perhaps he'd like to have a turn at being head of the house once he's finished his GCSEs?

'Dad...' he says, 'just lend me the bloody money, OK?'

Fine, I say, though I don't mind telling him that his request comes on top of the two quid I had to find for our eight-year-old's junior bookclub, £18 for the lower school's wading tour of East Anglian waterways and a letter that has turned up from the school outlining this autumn's £600 (ha-ha!) trip to Rome, aimed at pupils eager to broaden their understanding of religious studies or parents eager to offload their belligerent teenagers after the long hot summer holidays.

Ah, how different from my own extramural encounter with classical Rome in the early Seventies, when the whole class was whisked out to the local cinema to see Julius Caesar! How novel, even back then, to see a film made in thrilling sepia. I make him go upstairs to turn off some of the 14 lights he is bound to have left on, then send him on his way, with strict instructions not to ring me for a lift when he misses his train in five minutes.

'Well, why can't I get a lift now?' he says.

'Have you any idea how much petrol costs?'

No, he has no idea, or at least no more than I have.

Then my wife arrives back from the supermarket with a convoluted tale of woe featuring Tesco's interesting new policy of sending all the bakers home the minute you want someone to put a loaf of bread through the slicer.

'And this is on a Saturday afternoon!' she says, burdening me with a selection of their carrier bags that split all the time and telling me how she had to abandon her trolley and QUEUE for 10 minutes at customer services before demanding to know in her quiet but firm voice why it's like the Marie Celeste down there, and how they make billions a year but you can't get a loaf of sliced white on the busiest day of the week, unless you want the horrible processed stuff they have stacked up to the ceiling, so why bother cutting any of the nice fresh bread, right?

No, the woman says, the machine isn't working, that's all - though how you can tell is anyone's guess, my wife is now saying, because isn't it like that every week trying to find someone in a white coat?

Yes, I say, though I am more interested in how much she has spent, because I'm seeing organic tomatoes in there, which are not a known remedy for pecuniary ill-health. But my wife is now telling me how she's no sooner got half her shopping on the conveyor than the checkout woman decides to call it a day herself, or does until she refuses to budge (my wife, not the woman), because by now she's had enough. 'And to cap it all,' she says, 'I got to the petrol pump and it wouldn't take my card!'